It is known from EP 0 649 494 B1, incorporated by reference herein, to vary a sound level and/or a tone of an exhaust noise by means of a throttle flap positioned in an exhaust line.
It is also known from EP 1 982 055 B1, incorporated by reference herein, for a drive of a throttle flap positioned in the exhaust line to be activated by means of a signal generator in a targeted manner such that the throttle flap generates a desired frequency spectrum through additional sound generation.